The authors collected a series of 236 cases of multiple personality disorder patients reported to them by 203 clinicians throughout North America. The series included 81 patients who had received a past diagnosis of schizophrenia and 96 who had not. The patients with a past diagnosis of schizophrenia were more self-destructive and spent more time in the mental health system prior to diagnosis. During this period they received more other psychiatric diagnoses and treatments. They had more Schneiderian first-rank symptoms but did not have more auditory hallucinations.